Polyoxometalate‐Cyclodextrin‐Based Cluster‐Organic Supramolecular Framework for Polysulfide Conversion and Guest–Host Recognition in Lithium‐sulfur Batteries

Abstract

AbstractDeveloping polyoxometalate‐cyclodextrin cluster‐organic supramolecular framework (POM‐CD‐COSF) still remains challenging due to an extremely difficult task in rationally interconnecting two dissimilar building blocks. Here we report an unprecedented POM‐CD‐COSF crystalline structure produced through the self‐assembly process of a Krebs‐type POM, [Zn2(WO2)2(SbW9O33)2]10−, and two β‐CD units. The as‐prepared POM‐CD‐COSF‐based battery separator can be applied as a lightweight barrier (approximately 0.3 mg cm−2) to mitigate the polysulfide shuttle effect in lithium‐sulfur batteries. The designed Li−S batteries equipped with the POM‐CD‐COSF modified separator exhibit remarkable electrochemical performance, attributed to fast Li+ diffusion through the supramolecular channel of β‐CD, efficient polysulfide‐capture ability by the dynamic host–guest interaction of β‐CD, and improved sulfur redox kinetics by the bidirectional catalysis of POM cluster. This research provides a broad perspective for the development of multifunctional supramolecular POM frameworks and their applications in Li−S batteries.